Therapeutic Benefits of Natural Ingredients for Atopic Dermatitis

Anti-Inflammatory Response of New Postbiotics in TNF-α/IFN-γ-Induced Atopic Dermatitis-like HaCaT Keratinocytes

This study examines the synergistic interaction between the immunomodulatory functions of lactic acid bacteria postbiotics and the anti-inflammatory properties of Smilax china L. extract through a combined fermentation process. Using atopic dermatitis (AD) as a model, characterized by an immune imbalance that leads to skin inflammation, we developed a fermented product, MB-2006, and compared its effects to those of the heat-killed probiotics Lactobacillus acidophilus (LAC) and Lactobacillus rhamnosus (LRH). Our experiments focused on elucidating the mechanism of action of MB-2006 in AD-like HaCaT keratinocyte cells, particularly its impact on the NF-κB pathway, a pivotal regulator of inflammation. MB-2006 proved more effective in reducing inflammation markers, such as IL-4 and thymic stromal lymphopoietin (TSLP), and in inhibiting NF-κB activation compared to LAC and LRH. Significantly, MB-2006 also reduced the expression of thymus- and activation-regulated chemokine (TARC), highlighting a synergistic effect that enhances its therapeutic potential. These results suggest that the combined fermentation of Smilax china L. extract with lactic acid bacteria enhanced both the anti-inflammatory and immunomodulatory effects, presenting a promising integrative approach to treating conditions like AD. Further studies are needed to validate these results in clinical settings and fully explore the potential of this synergistic fermentation process.

Benefits of topical natural ingredients in epidermal permeability barrier

Because of the crucial role of epidermal permeability barrier in regulation of cutaneous and extracutaneous functions, great efforts have been made to identify and develop the regimens that can improve epidermal permeability barrier function. Studies have demonstrated that oral administration of natural ingredients can improve epidermal permeability barrier in various skin conditions, including inflammatory dermatoses and UV-irradiation. Moreover, topical applications of some natural ingredients can also accelerate the repair of epidermal permeability barrier after acute barrier disruption and lower transepidermal water loss in the intact skin. Natural ingredient-induced improvements in epidermal permeability barrier function can be attributable to upregulation of keratinocyte differentiation, lipid production, antioxidant, hyaluronic acid production, expression of aquaporin 3 and sodium-hydrogen exchanger 1. In this review, we summarize the benefits of topical natural ingredients in epidermal permeability barrier in normal skin with or without acute barrier disruption and the underlying mechanisms.

Recent Trends in Nanocarriers for the Management of Atopic Dermatitis

BACKGROUND

Atopic dermatitis (AD) is a pruritic inflammatory skin condition with increasing global prevalence, almost affecting 15% to 30% of children and 5% of adults. AD results due to a complex interaction between the impaired skin barrier function, allergens, and immunological cells. Topical corticosteroids or calcineurin inhibitors in the form of creams or ointments are the mainstay of therapy, but they have low skin penetration and skin barrier repair efficiency.

OBJECTIVE

The above limitations of conventional dosage forms have motivated the development of nanoformulations of drugs for improved penetration and deposition in the skin for better management of AD.

METHODS

Databases, such as Pubmed, Elsevier, and Google Scholar, were reviewed for the investigations or reviews published related to the title.

RESULTS

The present review discusses the advantages of nanoformulations for the management of AD. Further, it also discusses the various types of topically investigated nanoformulations, i.e., polymeric nanoparticles, inorganic nanoparticles, solid lipid nanoparticles, liposomes, ethosomes, transfersomes, cubosomes, and nanoemulsion for the management of atopic dermatitis. In addition, it also discusses advancements in nanoformulations, such as nanofibres, nanosponges, micelles, and nanoformulations embedded textiles development for the management of AD.

CONCLUSION

The nanoformulations of drugs can be a better alternative for the topical management of AD with enhanced skin penetration and deposition of drugs with reduced systemic side effects and better patient compliance.

Anti-Allergic Effects of Fermented Red Ginseng Marc on 2,4-Dinitrochlorobenzene-Induced Atopic Dermatitis-like Mice Model

Atopic dermatitis (AD) is a chronic and allergic skin disease; however, there is no cure for the disease. Red ginseng is well known to have anti-AD potential, while red ginseng marc (RGM) remaining after ginseng extraction is regarded as useless and discarded. However, it has recently been reported that RGM, particularly fermented RGM (fRGM), still contains bioactive properties. Thus, the anti-allergic effects of fRGM were examined in a 2,4-dinitrochlorobenzene-induced AD-like mice model. The model was topically treated with distilled water (control), dexamethasone, or fRGM for six weeks. Treatments of fRGM alleviated skin lesions and reduced serum IgE levels, compared with the control. The fRGM also reduced skin levels of lipid peroxidation and superoxide anion; however, it increased glutathione contents, with downregulated gene expression for inflammatory mediators. Histopathological analyses demonstrated that fRGM suppressed epidermal thickening, collagen deposition, and inflammatory cell and mast cell infiltration, which involved anti-inflammatory, antioxidant, and anti-apoptotic effects. Further, fRGM suppressed hypertrophic changes and inflammatory responses in the spleen and lymph nodes. The beneficial effects were observed in the dexamethasone and fRGM groups; however, the antioxidant effects were evident only in the fRGM treatments. These results provide useful information for developing fRGM as a therapeutic source for AD.

Osthole Inhibits Expression of Genes Associated with Toll-like Receptor 2 Signaling Pathway in an Organotypic 3D Skin Model of Human Epidermis with Atopic Dermatitis

The Toll-like receptor (TLR) family signature has been linked to the etiopathology of atopic dermatitis (AD), a chronic inflammatory skin disease associated with skin barrier dysfunction and immune system imbalance. We aimed to investigate whether osthole (a plant-derived compound) can inhibit the genetic profile of key genes associated with TLR2 signaling (TIRAP, MyD88, IRAK1, TRAF6, IκBα, NFκB) after stimulation with LPS or histamine in a 3D in vitro model of AD. Overexpression of the aforementioned genes may directly increase the secretion of proinflammatory cytokines (CKs) and chemokines (ChKs), which may exacerbate the symptoms of AD. Relative gene expressions were quantified by qPCR and secretion of CKs and ChKs was evaluated by ELISA assay. LPS and histamine increased the relative expression of genes related to the TLR2 pathway, and osthole successfully reduced it. In summary, our results show that osthole inhibits the expression of genes associated with the TLR signaling pathway in a skin model of AD. Moreover, the secretion of CKs and ChKs after treatment of AD with osthole in a 3D skin model in vitro suggests the potential of osthole as a novel compound for the treatment of AD.

Anti-allergic actions of a Chinese patent medicine, huoxiangzhengqi oral liquid, in RBL-2H3 cells and in mice

CONTEXT

Huoxiangzhengqi oral liquid (HXZQ-OL), a traditional Chinese medicine formula, has antibacterial, anti-inflammation and gastrointestinal motility regulation effects.

OBJECTIVE

The study investigates the anti-allergic activity and underlying mechanism of HXZQ-OL.

MATERIALS AND METHODS

IgE/Ag-mediated RBL-2H3 cells were used to evaluate the anti-allergic activity of HXZQ-OL (43.97, 439.7 and 4397 μg/mL) in vitro. The release of cytokines and eicosanoids were quantified using ELISA. RT-qPCR was used to measure the gene expression of cytokines. The level of intracellular Ca²⁺ was measured with Fluo 3/AM. Immunoblotting analysis was performed to investigate the mechanism of HXZQ-OL. In the passive cutaneous anaphylaxis (PCA), BALB/c mice (5 mice/group) were orally administrated with HXZQ-OL (263.8, 527.6 and 1055 mg/kg/d) or dexamethasone (5 mg/kg/d, positive control) for seven consecutive days.

RESULTS

HXZQ-OL not only inhibited degranulation of mast cells (IC₅₀, 123 μg/mL), but also inhibited the generation and secretion of IL-4 (IC₅₀, 171.4 μg/mL), TNF-α (IC₅₀, 88.4 μg/mL), LTC4 (IC₅₀, 52.9 μg/mL) and PGD2 (IC₅₀, 195.8 μg/mL). Moreover, HXZQ-OL suppressed the expression of IL-4 and TNF-α mRNA, as well as the phosphorylation of Fyn, Lyn and multiple downstream signalling proteins including MAPK and PI3K/NF-κB pathways. In addition, HXZQ-OL (527.5 mg/kg) attenuated the IgE-mediated PCA with 55% suppression of Evans blue exudation in mice.

CONCLUSIONS

HXZQ-OL attenuated the activation of mast cell and PCA. Therefore, HXZQ-OL might be used as an alternative treatment for allergic diseases.

Cera Flava Alleviates Atopic Dermatitis by Activating Skin Barrier Function via Immune Regulation

Cera Flava (CF), a natural extract obtained from beehives, is widely used in dermatological products owing to its wound healing, wrinkle reduction, UV-protective, and skin cell turnover stimulation effects. However, its effect on AD-like skin lesions is unknown. In this study, we used a mouse model of AD to evaluate the effects of CP at the molecular and phenotypic levels. Topical house dust mite (HDM) sensitization and challenge were performed on the dorsal skin of NC/Nga mice to induce AD-like cutaneous lesions, phenotypes, and immunologic responses. The topical application of CF for 6 weeks relieved HDM-induced AD-like phenotypes, as quantified by the dermatitis severity score, scratching frequency, and skin moisture. CP decreased immunoglobulin E, histamine, and thymic stromal lymphopoietin levels. Histopathological analysis showed that CF decreased epidermal thickening and the number of mast cells. CF attenuated HDM-induced changes in the expression of skin barrier-related proteins. Furthermore, CF decreased the mRNA levels of inflammatory factors, including interleukin (IL)-1β, IL-4, IL-13, IL-8, TARC, MDC, and RANTES, in dorsal skin tissue via the TLR2/MyD88/TRAF6/ERK pathway. CF influences skin barrier function and immune regulation to alleviate AD symptoms. It may therefore be an effective alternative to topical steroids for the treatment of AD.

Anti-inflammatory effects of Capparis ecuadorica extract in phthalic-anhydride-induced atopic dermatitis of IL-4/Luc/CNS-1 transgenic mice

CONTEXT

The natural products derived from Capparis ecuadorica H.H. Iltis (Capparaceae) could have great potential for anti-inflammation since they inhibited the inflammatory response in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells.

OBJECT

This study investigated the anti-inflammatory effects and related mechanism of methanol extract of C. ecuadorica leaves (MCE) during atopic dermatitis (AD) responses.

MATERIALS AND METHODS

Alterations in the phenotypical markers for AD, luciferase signal, iNOS-mediated COX-2 induction pathway, and inflammasome activation were analysed in non-Tg (n = 5) and 15% phthalic anhydride (PA) treated IL-4/Luc/CNS-1 transgenic (Tg) HR1 mice (n = 5 per group), subsequent to treatment with acetone-olive oil (AOO), vehicle (DMSO) and two dose MCE (20 and 40 mg/kg) three times a week for 4 weeks.

RESULTS

MCE treatment reduced the intracellular ROS level (48.2%), NO concentration (7.1 mmol/L) and inflammatory cytokine expressions (39.1%) in the LPS-stimulated RAW264.7 cells. A significant decrease was detected for ear thickness (16.9%), weight of lymph node (0.7 mg), IgE concentration (1.9 µg/mL), and epidermal thickness (31.8%) of the PA + MCE treated Tg mice. MCE treatment induced the decrease of luciferase signal derived from the IL-4 promoter and the recovery of the IL-4 downstream regulator cytokines. PA + MCE treated Tg mice showed decreasing infiltration of mast cells (42.5%), iNOS-mediated COX-2 induction pathway, MAPK signalling pathway and inflammasome activation in the ear tissue.

CONCLUSIONS

These findings provide the first evidence that MCE may have great potential to suppress chemical-induced skin inflammation through the suppression of IL-4 cytokine and the iNOS-mediated COX-2 induction pathway, and activation of inflammasome.

Laminaria japonica Suppresses the Atopic Dermatitis-Like Responses in NC/Nga Mice and Inflamed HaCaT Keratinocytes via the Downregulation of STAT1

Atopic dermatitis (AD) is a skin allergy accompanied by acute and chronic dermal inflammation. In traditional oriental medicine, Laminaria japonica has been used to treat various diseases, including inflammatory diseases. Therefore, to determine the therapeutic potential of L. japonica against AD, we investigated the inhibitory effects of L. japonica water extract (LJWE) on the inflammatory mediators and AD-like skin lesions. We determined the cell viability of LJWE-treated HaCaT cells using the cell counting kit-8 assay and the levels of inflammatory cytokines using cytometric bead array kits. Additionally, we analyzed the modulatory effects of LJWE on the signaling pathways in tumor necrosis factor-α/interferon-γ-stimulated HaCaT cells via Western blotting. Furthermore, we determined the in vivo effect of LJWE on NC/Nga mice and found that LJWE remarkably improved the skin moisture, reduced dermatitis severity, and inhibited the overproduction of inflammatory mediators in 2,4-dinitrochlorobenzene-sensitized NC/Nga mice. We also observed that LJWE inhibits the expression of inflammatory chemokines in human keratinocytes by downregulating the p38 mitogen-activated protein kinase signaling pathway and activating the signal transducer and activator of transcription 1. In conclusion, LJWE has the therapeutic potential against AD by healing AD-like skin lesions, and suppressing inflammatory mediators and major signaling molecules.

Anti-inflammatory effect of bee venom in phthalic anhydride-induced atopic dermatitis animal model

Globally, many people have been affected with atopic dermatitis (AD), a chronic inflammatory skin disease. AD is associated with multiple factors such as genetic, inflammatory, and immune factors. Bee venom (BV) is now widely used for the treatment of several inflammatory diseases. However, its effect on 5% phthalic anhydride (PA)-induced AD has not been reported yet. We investigated the anti-inflammatory and anti-AD effects of BV in a PA-induced animal model of AD. Balb/c mice were treated with topical application of 5% PA to the dorsal skin and ears for induction of AD. After 24 h, BV was applied on the back and ear skin of the mice three times a week for 4 weeks. BV treatment significantly reduced the PA-induced AD clinical score, back and ear epidermal thickness, as well as IgE level and infiltration of immune cells in the skin tissues compared to those of control mice. The levels of inflammatory cytokines in the serum were significantly decreased in BV-treated group compared to PA-treated group. In addition, BV inhibited the expression of iNOS and COX-2 as well as the activation of mitogen-activated protein kinase (MAPK) and NF-ҡB induced by PA in the skin tissues. We also found that BV abrogated the lipopolysaccharide or TNF-α/IFN-γ-induced NO production, expression of iNOS and COX-2, as well as MAPK and NF-ҡB signaling pathway in RAW 264.7 and HaCaT cells. These results suggest that BV may be a potential therapeutic macromolecule for the treatment of AD.